Condenser



v Feb. 2l, 1933. A c. RINGWALD 1,898,789

CONDENSER Filed Nov. 5, 1927 2 Sheets-Sheet l Feb. 21, 1933. I C,RINGWALD 1,898,789

CONDENSER Filed Nov. 3, 1927 2 Sheets-Shee'f 2 Ca rence Fi'ngwa/a/Patented Feb. 2l, 1933 UNITED STATES CLARENCE BINGWALD, Ol' SOUTH BEND,INDIANA CON DENSIR Application lled November 8, 1987. ySerlll No.830,784.

the two layers or strips of conducting material, such as tinfoil, or thelike, upon a mandrel which may form a core and serve as one of thecondenser terminals. One of the conducting strips or layers is incontact or connected with the core, and the two i conducting strips orlayers are insulated from each other by insulating wrappings interposedtherebetween.

The layers or strips of tinfoil, or other 5 conducting material, arepreferably so minals o wound that the ed e of one strip projects fromone edge of the insulatinr wrappings with the ed e of the otherconducting strip projecting rom the op osite edge of said insulatingwrappings. he projecting edge of tne strip is crushed over, connectingthe turns or convolutions of one conducting strip at one end, and theprojectin edge of the other strip is crushed over an into contact withthe core to connect the turns or convolutions of the other strip witheach other and with the core at the opposite end of the condenser.

The condenser may be enclosed within a surrounding cup or casing and theconducting stri not connected with the core may be suita ly connectedwith this casing, the present invention providing an improved anchorinof the connecting leads orterthe condenser.

The improved method of winding reduces the number of rolls required, andit also gives more mechanical strength. to the paper or insulationassembly in the winding, makes o it easier to guide and handle the same,and

provides a condenser which is free from wrinkles and air pockets whichare extremely detrimental.

e improved insulating layer or wrapping improves the insulation' andprovides 555 a superior condenser. I am unable to state with certaintythe exact action or actions to which the improvement is due, but I shalldescribe in the followin detailed specification how this aspect of teinvention may be 603 practiced and employed, and I shall reserve theright to propound, supplement or correct the theory as soon as I becomeaware of the same.

The invention is illustrated in the accom- 555 panying drawings inwhich:

Figure 1 is a longitudinal section taken axial y through a condenserembodying the present invention before applying the enclosing cup orcasing and showing one manner of winding the condenser;

Fig. 2 is a similar view through a completed condenser embodying thepresent invention;

Fig. 3 is a transverse section taken on the line 3 3 of Fig. 2;

Fig. 4 is an enlarged fragmentary longitudinal section taken axiallythrough one end and showing the projecting edge of one conducting stripor layer crushed together and into contact with the core;

Fig. 5 is a similar view through the opposite end of the condensershowing the projecting edge of the other conducting strip crushedtogether and the anchoring of the leaids or terminals of the condenserat that en Fig. 6 is a fragmentary more or less diagrammatic elevationalview, showing the anchoring of the leads or terminals just referred to;and

Fig. 7 is a more or less diagrammatic view showing the preferred mannerof Winding the condenser.

Referring to the drawings, a conducting core l0, preferablv of brass,although it may be of any other suitable or preferred metal, is providedwith a reduced cylindrical end 11 and its opposite end is bored andinternally threaded at 12. One end of the core 10 is moulded at 13 intoan end piece 14 formed of a condensation product, or other suitableinsulating material, the core 10 being preferably reduced at 15 to bindit firmly in the end piece 14 and against endwise displacement.

The core is preferably of polygonal cross section, although adifferently shaped core may be employed. The particular core showngreatly facilitates the work of winding by reason of the ease with whichit takes hold of the various strips or layers, and the axial hub 16 ofthe end piece 14 is preferably similarly shaped.

According to the present invention the core 10 is adapted to serve asthe winding mandrel and the core may, therefore, be

ymounted in a suitable condenser winding machine with the internallythreaded bore 12 threaded onto the driving spindle A and with thereduced end 11 supported by the idle center B of the winding machine, asindicated diagrammatically in Fig. 1.

The core 10 is rotated, as indicated by the arrow in F ig. 7, to windthereon two strlps of foil or other suitable conducting material 20 and21 separated by two insulating layers or Wrappings 22.

Each layer or winding of insulation 22 preferably comprises two sheetsor strips 23. 23 of paper with a sheet, strip or layer 24 of differentpaper between them. As merely illustrative of this, a layer of tissue orother suitable paper might be used between two sheets of glazed paper,but this may, of course, be varied widely. It seems that the twodifferent papers or grades of paper, having different fiber structure,will retain the wax or insulating compound in definite crystalline formin relation to each individual paper construction. It seems that thispermits higher insulation than if the crystals form always in one way,but as already pointed out, I am unable to state with certainty thetheory of action by which the improved result is secured, and I reservethe right to propound the correct theory as soon as I become aware ofthe same.

The paper or insulating layers 22 of which there are two, as shown inFig. 7, are unwound from two rolls 25 and 26 and the two "foil orconducting strips or layers 20 and 21 lated condenser it would benecessarv to,

handle eight rolls. There is a great deal of V,diiiculty in obtaininguniform tension on such a number of rolls and also the paper of theindividual rolls has a certain amount of tension within itself. Byreducin the number of rolls to two, or to a sing e roll for each layeror convolution of insulation, whether it comprises three or any otherplurality of sheets or strips, these disadvantages are overcome. Moremechanical strength to the paper assembly in the Winding is also securedand it is easier to guide and handle, and the condenser is made up freefrom wrinkles or air pockets .with their disadvantages.

In Winding the condenser one or more turns of the foil strip 20 may befirst wound directly upon the metal core 10 to place this] strip indirect electrical contact with the core. Then one of the insulatinglayers may be wound onto the core sufiiciently to completely cover thefirst turn or turns of the foil strip 20. whereupon the second foil strior layer 21 is started upon the mandrel wit the next layer of insulation22 around it to insulate it from the other foil strip. The core 10 maythen be rotated to wind on all of the material simultaneously until thede- :sired number of turns are applied.

Upon completing the Winding the inner foil strip is preferably severedcloser to the core than the other foil strip, so that the outer ends ofthese strips Will be se arated from each other and a few turns owrapping paper may be wound about the condenser as desired. The freeends of the strips or layers may be pasted or otherwise secured down.

' The foil or conducting layer 20 is so wound that the edge 32, as shownin dotted lines in Fig. 4, projects axially from one end of the cylinderformed by the various windings, and the edge 34 of the other strip, asshown in dotted lines in Fig. 5, projects from the opposite end of thecondenser. The projecting edge 32 is crushed together, as shown in Fig.4, and up into contact at 35 with the reduced end 11 and adjacentshoulder of the core 10. This connects the ends of the turns of oneconducting layer with each other and With the core 11 at one end and theopposite ends of the conducting layer 21 are crushed together, as at 21(Fig. 5), thereby connecting the ends of the turns of the otherconducting layer at the opposite end of the condenser. Where the ends 32of the foil strip 20 are turned over at one end, the adjacent edge ofthe other foil strip 21 is preferably spaced from or terminates short ofthe adjacent edge of the insulation 22, as at 30, and viceversa at theopposite end to prevent electrical contact between the two foil stripsat the ends of the condenser. The current may, therefore, flow axiallythrough the condenser and will not have to flow in a circular direction,and the amount of induction will thereby be decreased.

The-ends of the foil strips may be crushed together durin or afterwindin the condenser and while the ends 21 ig. 5) are Vshown as turnedoutwardly, they may be turned inwardly or otherwise crushed into contactat the end of the condenser, as desired. The wound condenser may beimmersed, dipped, or otherwise impregnated with wax, or other suitableor preferred insulating material or compound to protect the windingsfrom moisture and insure a constant capacity in the condenser. Thecylindrically wound unit may, in this manner, be firmly consolidatedtogether.

After 'winding the insulating and conducting layers upon the centralcore 10, crushlconducting layers together, and dipping or otherwisetreating the resulting structure with wax or other suitable insulatingmaterial, the condenser is placed within a condenser casing or cup 40.This cup 40 while preferably of brass, may be of any other suitablemetal or conducting material, and -it is of generally cylindricalformation with an integral closed end 42 and an open end 43. Theinsulatin end piece 14 abuts and closes the open end of the cu 40, andthis end piece 14 is provided wit an annular metallic piece of tin orother suitable or preferred sheet metal 45 which may be moulded alongits inner margin in the end 'piece 14. This annular metallic piece 45may extend radially as shown in dotted lines in Fig. 1, and uponapplying the vcup or casing 40 the margin of the annular piece 45 isturned at 46 over the adjacent end of the casing 40, and it may besoldered or otherwise suitably secured thereto at 60.

The central core 10 serves as one of the condenser terminals and abinding or terminal screw 50 may be threaded into the internally boredand threaded end 12. The shankv of this screw may be provided with asplit or spring washer 52.

The conducting windin which is connected electrically with tile centralcore 10 is insulated at 'its opposite end from the cup 40, and theconducting winding 21 may be connected electrically with the metalliccup 40, as by means of a pair of suitable terminals or leads 53.

The terminals or leads 53, 53 comprise relatively thin copper or othersuitable conducting strips, laid inicontact with the foil strip or layer21 in winding the condenser of the condenser as they are wound in lace.The inner or anchored ends of the lea s 53, 53 are laid between theconducting layer 21 and the .adjacent insulating layer 22, eitherbetween the same turns or convolutions ing or flattening the oppositeends of the and bound in place by the successive turnsA thereof or oneinwardly with reference to the radius of the condenser as shown in Fig.6.

To improve the attachment of the leads 53, 53, the anchored ends may behooked at D 55, 55 (Fig. 6). The hooking of the ends '70 55, 55 disposesthese ends out of continuity with the leads and, as the condenserwrappings are applied, the hooked ends 55 are wound partially about thefoil strip 21 with which they are in contact. This increases the bindingaction upon these ends and disposes some of the bindingaction at leastout of the direct line of pull oroutward displacement of the leads,tying and binding the inner anchored ends of the leads more effectivelyagainst being accidentally pulled out or displaced than where theanchored ends are merely straight continuations of the terminal leads orstrips.

The outer projecting ends'of the leads 53, 53 project from-the end ofthe condenser and may be grounded through the metal cup 40. Theconnection of the project-ing ends of the leads 53 with the cup 40 maybe provided by soldering these ends to the metallic piece 45 beforeturning it marginally over the open end of the cup 40, and when saidpiece 45 is turned marginally over the open end of the cup 40 andsoldered at 60 thereto, the strip 21 is connected through the leads 53,53 with the cup 40 which serves as one of the condenser terminals andmay, for example, be connected to ground.

The outer end of the core 10 serves as the other terminal and,obviously, the manner of connecting the projecting ends of the strip 20together and to the core 10, and the opposite projecting ends of thestrip 21 together and to the cup 40, permits the current to flow axially1n the cylinder of the condenser so that it will not have to flow in acircular direction and there will, consequently, be little orpractically no induction caused by the current.

The condenser is weather-proof and the structure and method of making upor producing the same are simple, economical and ex editions.

claim 1. In a condenser, the combination of a 116 metallic core, a pairof conducting strips wound upon said core with interposed layers ofinsulation between them and with one strip connected with said core, aterminal connection at one end of said core, the op- 120 lis lposite endof said core having connection with the edges of the turns of saidconducting strip at one end, a surrounding casing, and means connectingthe turns of the other conducting strip with said casing at the oppositeend.

2. In a condenser, the'combination of a metallic core, a pair ofconducting strips wound upon said core with interposed layers ofinsulation between them and with one 13(` strip connected with saidcore, a terminal connection at one end of said core, the opposite end ofsaid corehaving connection with the edges of the turns of saidconducting strip at one end, a surrounding casing, means connecting theturns of the other conducting strip with said casing at the oppositeend, said casing comprising a metallic cup closed at one end and open atthe opposite end, and an insulating end piece on the core and closingthe open end of said cup.

3. In a condenser, the combination of a metallic core, a pair ofconducting strips wound upon said core with interposed layers ofinsulation between them and with one strip connected with said core, asurrounding casing comprising a metallic cup closed at one end and openat the opposite end,

' an insulating end piece moulded upon said core and closing the openend of said cup, the inner end of said core having connection with theedges of the turns of said conducting strip, the other conducting striphaving the edges of its turns connected together at the opposite end andhaving connection wtih said cup.

' 4. In a condenser, the combination of a metallic core, a pair ofconducting strips wound upon said core with interposed layers ofinsulation between them and with one strip connected with said core, asurrounding casing comprising a metallic cup closed at one end and openat the opposite end, an insulating end piece moulded upon the core forthe open end of the cup, and an annular metallic piece moulded in saidend piece ,and turned marginally over the adjacent end of the casing.

5. In combination, a condenser having a metallic core, a casingenclosing said condenser, an insulating end piece for said casing, saidend piece being moulded upon said core, and an annular metallic piecemoulded in said end piece and turned marginally over the adjacent end ofthe casing.

6. In combination, a condenser having a metallic core, a casingenclosing said condenser and provided with an open end, and aninsulating end piece moulded upon said core and closing the open end ofsaid casing.

7 In a condenser having conducting and insulating layers wound intocylindrical form, the combination of a lead having a hooked end laidbetween the windings of the condenser and connected with a conductinglayer of the condenser.

8. In a condenser, the combination of a metallic core having a recessnear one end, a pair of conducting strips with interposed layers ofinsulation between them wound upon said core and partially over saidrecess, and an insulating end piece moulded upon said core and into saidrecess.

9. In a condenser, the combination of a metallic core having a recessnear one end,

a pair of conducting strips with interposed layers of insulation betweenthem wound upon said core and partially over said recess, an insulatingend piece moulded upon said core and into said recess, a metallic piecemoulded in said end piece, one of said conducting strips havingconnection with said core and the other conducting strip havingconnection with said metallic piece.

In witness whereof, I hereunto subscribe my name this 27th day ofOctober, 1927.

CLARENCE RINGWALD.

